We report on the analysis of new X-ray data obtained
with XMM-Newton and Chandra from two ROSAT-discovered X-ray dim
isolated neutron stars (XDINs). was observed with XMM-Newton
in April 2003, 2.5 years after the first observation. The EPIC-pn
data confirm that this object is an X-ray pulsar with 11.371 s
neutron star spin period. The X-ray spectrum is consistent with
absorbed black-body emission with a temperature eV and
NH = 4 cm-2 without significant changes between the two
observations. Four XMM-Newton observations of between
December 2002 and July 2003 did not confirm the 22.7 s pulsations
originally indicated in ROSAT data, but clearly reveal a 3.453 s
period. A fit to the X-ray spectrum using an absorbed black-body
model yields eV, the lowest value found from the small
group of XDINs and NH = 1.0 cm-2. Including a broad
absorption line improves the quality of the spectral fits considerably
for both objects and may indicate the presence of absorption
features similar to those reported from , and .
For both targets we derive accurate X-ray positions from the
Chandra data and present an optical counterpart candidate for
with mag from VLT imaging.

Based on observations with XMM-Newton, an ESA Science Mission
with instruments and contributions directly funded by ESA Member
states and the USA (NASA). Optical observations were performed at the European
Southern Observatory, ESO programme 66.D-0128(A).

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